Zinnia bicolor as Natural pH Indicator

Acid-base indicators shows change in color after change in pH of medium, and the flower extract of various plants shows sharp color change with change in pH of reacting medium. The study has been carry out to replace the synthetic indicator with zinnia flower extract, because synthetic acid base indicators have some disadvantages like complicated method of preparation, high cost and they may causes the environmental pollution or may cause harm to user. The ethanolic extract of zinnia flower is done to determine the indicator activity of zinnia flower and compared with phenolphthalein indicator. Four deferent types of neutralization titrations like HCl Vs NaOH, HCl Vs NH3, CH3COOH Vs NaOH, and CH3COOH Vs NH3 are done to get precise and accurate results. This research work proves that we can use zinnia flower extract as a substitute for synthetic acid base indicator in various acid-base titrations.